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Can you summarize what they said about charging with R414b in #4 & #5? Is it about the danger of overcharging if you clear the sightglass?

icemeister, Here's my experience with 414b. I worked for a contractor years ago who jumped on the Hot Shot bandwagon. It seemed to work well with med temp walkins. and coolers/freezers with static coils(always bubbles in the sight glass with static coils). If a unit had multiple metering devices, it was damn near impossible to get them balanced out, moreso if they were converted from 409a to 414b, rather than from 12 to 414b. I prefer to use 409a, 134a, or just sell them new equipment. MP 39 is not too popular around my parts although I do run into it once in awhile. It seems to perform pretty well.

Officially, Down for the count

YOU HAVE TO GET OFF YOUR ASS TO GET ON YOUR FEET

I know enough to know, I don't know enoughLiberalism-Ideas so good they mandate them

Icor stresses it. Especially on mobile equipment. It's on every piece of literature I've seen. I don't know if this is still true but years ago Copeland wouldn't honor warranty claims if they had been running 414b.

Officially, Down for the count

YOU HAVE TO GET OFF YOUR ASS TO GET ON YOUR FEET

I know enough to know, I don't know enoughLiberalism-Ideas so good they mandate them

1) RLA is closed to the FLA, but not the same, RLA is usually a rating given by the manufacturer of the ampere the compressor should run, and FLA is the maximum ampere the compressor should be running
2) usually RLA is just slightly below FLA
4) filter drier, as the name said, it's for filtering purpose, and it is required in many systems to prevent damage to the compressor, but it should be the same charge you would need as if you didn't put it in
5) I've read many posts online saying that you need to fill freon till the glass is clear, and that is wrong practice when it comes to the field. If the unit is working as it should with everything else check, even if the sight glass has slightly bubble, it is fine. This could be due to the unit is not sized correctly, even so, it will still run at near optimal if everything else is correct.

You can't correctly sub cool with a mixture of liquid and vapor, you must have a solid column of liquid all the way to the TXV.
Gas it up and let it shut down while you monitor system pressures, SH, SC, amp draw. Adjust from there if necessary.

I thought a mix of liquid and vapor was the point of saturation, thus cooling that saturated mix below the saturation point (PT Chart will help for this) is "SubCooling." Just sayin... Sub cooling happens at the condenser and should be all liquid at the outlet up to the metering device. I believe that is what you meant.

I installed a matched system walk in equipment sized by Larkin engineers if you clear the sight glass that puppy is over charged ! set super heat at 8degrees still have bubbles dont be afraid of bubbles with 404a

Years ago you never ran into systems with tevs and no receiver .i was always told tevs won't feed correctly without complete liquid at the inlet.also with no receiver liquid can back up in the condenser effectively shrinking it.

I see FLAs on motors and RLAs on compressors commonly. The load on compressor is constantly varying depending on the load and resistance on condenser.

The FLA of a fan motor is set by mating the fan with a motor that can handle the fan at the minimum anticipated static. The fan motor can't overload unless you run it outside of design specs, such as using an HVAC blower fan meant to work in an air handler in open air as a carpet dryer. It only goes down as static increases with dirt accumulation and returning to original spec when filters are replaced and everything cleaned up.

when you are working on a system that has been converted to Different Refrigerant , its a whole new ball game. Sometimes you will still have bubbles in this case , and although not perfect , it is what it is ....

But in a system that is charged with what it was designed for , I've never seen bubbles ( when all is working right )